subsp. subsp. nov., a psychrotolerant facultative anaerobe isolated from a cold spring.

A psychrotolerant facultative anaerobe, strain SKBG, was isolated from the bottom sediments of the cold mineral spring Buxichen (Buryatia, Russia). Gram-positive non-motile cocci with a diameter of 1.75-2.5 µm were observed singly or in long chains. Cells grew in the temperature range from ̶ 5-35 °C. Growth was observed within the pH range of 7.0-9.5, with the optimum growth at pH 7.6 and at a NaCl concentration from 0-1.0 % (optimum 0.1 % (w/v)). Strain SKBG was a chemoorganoheterotroph that used sugars and some organic acids as substrates. The predominant fatty acids in cell walls were Сω9, Сω9, and С. The 16S rRNA gene sequence of strain SKBG shared high similarity (>99 %) with those of the type strains of the genus . Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values between strain SKBG and Art (=DSM 107162=VKM B-3260) were 70.1 and 95.4 %, respectively. The genomic DNA G+C content of strain SKBG was 47.1 mol%. Compared with the type strain of , the new strain was characterized by a temperature optimum for growth (10 °C) significantly lower than that of DSM 107162 (20-30 °C). Based on phenotypic and genomic characteristics, the isolate SKBG was classified as subsp. subsp. nov. The type strain is SKBG (=VKM B-3241=JCM 33326).